App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 279 · 40 questions

Developer's tip (Box, list, place): A variable holds one value; a list holds many in order. Positions start at 0. push adds to the end; pop takes off the last item; length is how many items. On the phone: works offline, private. In the cloud: shared, any device, needs the internet.

1. 1.Which of these fits saving in the cloud? (a) your last game level (b) the sound on/off setting (c) notes to read offline (d) a class leaderboard
2. 2.💾 Where should the app save a shared to-do list: on the phone or in the cloud? (a) on the phone (b) in the cloud
3. 3.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) the sound on/off setting (d) a class leaderboard
4. 4.💾 What is a variable? (a) a named box for a value (b) a phone setting (c) a type of screen (d) a picture
5. 5.💾 Which can hold many values in order? (a) a switch (b) a button (c) a single number (d) a list
6. 6.💾 What number does this code show?
   let points = 3;
   points = points - 3;
   points = points + 5;
   show(points);
7. 7.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) a draft you are typing (d) a shared to-do list
8. 8.💾 Saving data in the cloud lets you ___. (a) skip the internet (b) use it on any device (c) shrink the app (d) never need a password
9. 9.💾 pop() takes off the last item. What does this code show?
   let notes = ["Art", "Sports", "Maths"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Sports (b) Maths (c) Art
10. 10.💾 What number does this code show?
    let coins = 7;
    coins = coins - 2;
    coins = coins + 2;
    show(coins);
11. 11.💾 What number does this code show?
    let friends = ["Kabir", "Arjun"];
    friends.push("Riya");
    show(friends.length);
12. 12.💾 Data saved only on the phone is lost when ___. (a) the phone is lost (b) the screen turns off (c) you send a message (d) the app is closed
13. 13.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Sunrise", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Stars (c) Ocean
14. 14.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
15. 15.Which of these fits saving in the cloud? (a) chat messages to friends (b) your last game level (c) notes to read offline (d) a draft you are typing
16. 16.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Arjun", "Meera"];
    show(friends[2]); (a) Meera (b) Riya (c) Arjun
17. 17.True or false: notes to read offline fits saving on the phone. (a) False (b) True
18. 18.💾 What number does this code show?
    let coins = 4;
    coins = coins - 4;
    coins = coins + 4;
    show(coins);
19. 19.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
20. 20.💾 What number does this code show?
    let songs = ["Rain", "Stars"];
    songs.push("Sunrise");
    songs.push("Kites");
    show(songs.length);
21. 21.💾 What number does this code show?
    let stars = 9;
    stars = stars - 6;
    stars = stars + 5;
    show(stars);
22. 22.💾 What number does this code show?
    let friends = ["Aman", "Kabir", "Riya", "Zoya"];
    friends.push("Meera");
    friends.push("Arjun");
    show(friends.length);
23. 23.Which of these fits saving in the cloud? (a) a shared to-do list (b) your last game level (c) notes to read offline (d) a draft you are typing
24. 24.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
25. 25.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
26. 26.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
27. 27.💾 What number does this code show?
    let songs = ["Ocean", "Sunrise", "Stars"];
    songs.push("Rain");
    songs.push("Kites");
    show(songs.length);
28. 28.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
29. 29.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
30. 30.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Sunrise", "Ocean", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Monsoon (c) Sunrise (d) Rain
31. 31.💾 Which works with no internet at all? (a) a cloud backup (b) data saved on the phone (c) a cloud leaderboard (d) a shared chat
32. 32.💾 What number does this code show?
    let points = 6;
    points = points - 3;
    points = points + 3;
    show(points);
33. 33.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
34. 34.Which of these fits saving in the cloud? (a) notes to read offline (b) photos on two devices (c) a draft you are typing (d) your last game level
35. 35.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Riya", "Zoya"];
    show(friends[2]); (a) Zoya (b) Meera (c) Riya
36. 36.💾 What number does this code show?
    let stars = 5;
    stars = stars - 5;
    stars = stars + 3;
    show(stars);
37. 37.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
38. 38.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) on the phone (b) in the cloud
39. 39.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Ocean", "Stars"];
    show(songs[0]); (a) Stars (b) Ocean (c) Monsoon
40. 40.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone

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